Embodiments of the invention relate to an image sensor and a method of fabricating the same.
An image sensor is a semiconductor device that converts an optical image into electrical signals. Such an image sensor includes a micro-lens array that guides incident light toward a photodiode.
One factor to be solved in fabricating an image sensor is to increase a rate (e.g., the sensitivity) of converting incident light into electrical signals. Studies and research are being pursued to realize a zero gap in which no gap exists between lenses adjacent to each other in the micro-lens array.
However, in a method for manufacturing a CMOS image sensor, delamination of a capping layer may occur in a pad open section, the pad of which serves for signal connection with exterior signal lines, due to a stress difference between layers of and/or over the pad. Also, in a wafer back grinding process, a packaging process and the like, polymer particles derived from the photoresist layer and the like may be generated and may attach to the micro-lens array. Thus, the sensitivity of an image sensor can be lowered and the yield rate can be reduced due to the difficulty of cleaning the micro-lens array.